[compiler-rt] [RTSan] Fix tests under Internal Shell (PR #168470)

[Chris Apple via llvm-commits]

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@@ -8,18 +8,19 @@
 // RUN: %clangxx -fsanitize=realtime %s -o %t.so -shared -DSHARED_LIB
 // RUN: %clangxx %s -o %t
 
-// RUN: RTSAN_DYLIB_PATH=`%clangxx -fsanitize=realtime %s -### 2>&1 \
+// RUN: %clangxx -fsanitize=realtime %s -### 2>&1 \
 // RUN:   | grep "libclang_rt.rtsan_osx_dynamic.dylib" \
-// RUN:   | sed -e 's/.*"\(.*libclang_rt.rtsan_osx_dynamic.dylib\)".*/\1/'`
+// RUN:   | sed -e 's/.*"\(.*libclang_rt.rtsan_osx_dynamic.dylib\)".*/\1/' \
+// RUN:   | tr -d '\n' > %t.rtsan_dylib_path
 
 // Launching a non-instrumented binary that dlopen's an instrumented library should fail.
 // RUN: not %run %t %t.so 2>&1 | FileCheck %s --check-prefix=CHECK-FAIL
 // Launching a non-instrumented binary with an explicit DYLD_INSERT_LIBRARIES should work.
-// RUN: DYLD_INSERT_LIBRARIES=$RTSAN_DYLIB_PATH %run %t %t.so 2>&1 | FileCheck %s
+// RUN: env DYLD_INSERT_LIBRARIES="%{readfile:%t.rtsan_dylib_path}" %run %t %t.so 2>&1 | FileCheck %s
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cjappl wrote:

How is this file populated? (just so I understand for any future work I need to do regarding environment variables)

https://github.com/llvm/llvm-project/pull/168470